1851 census has this couple with 3 children and 1 Grandchild living at Limehouse, Middlesex:
William SPRINGATE c1778 Deptford, Kent HEAD Blacksmith
Susanah c1784 Deptford, wife
Charles c1819 Poplar, Middlesex unmarried, Blacksmith
Susanah c1823 Poplar unmarried Bonnet Maker
Henry c1825 Poplar unmarried Blacksmith
Alfred c1842 Putney, Surrey
Other possible children from baptism records where parents names are correct and William is a blacksmith:
Louisa born April 1813 baptised April 1813 at Rotherhithe St Mary, Southwark
Sophia Susannah born 31 March 1820 baptised as an adult 16 March 1835 same church
The only marriage I could find for the parents was William SPRINGATE to Susanna PUNYER 4 June 1805 at Aldington, Kent. But of course this might not be the correct marriage.
Family search has multiple entries for children John, Elizabeth, William & Susannah all at Aldington.